Ernährungs-Interventions-Fettleber-Studie (Interventional Study on Nutritional Effects on NAFLD) (UFOP-2)

Epidemiological data and studies in animal models suggest, that polyunsatured fatty acids (PUFA) rather than mono-unsatured fatty acids (MUFA) are associated with lower hepatic lipid content (HCL) and may facilitate a decrease of HCL in case of non-alcoholic fatty liver disease (NAFLD). The investigators therefore conduct an interventional trial in subjects with normal glucose metabolism, but increased HCL, fulfilling criteria for NAFLD. The study will compare two dietary interventions in parallel design, one containing mainly PUFA (canola oil), one containing only MUFA (olive oil). The intervention of 8 weeks is accomodated by dietary counseling. Metabolic outcome variables will be assessed with MR spectroscopy (liver fat) and euglycemic hepatic clamp (glucose metabolism/insulin sensitivity).

Epidemiological data and studies in animal models suggest, that polyunsatured fatty acids (PUFA) rather than mono-unsatured fatty acids (MUFA) are associated with lower hepatic lipid content (HCL) and may facilitate a decrease of HCL in case of non-alcoholic fatty liver disease (NAFLD). A typical source for PUFAs are fish and certain plant oils, a source of almost pure MUFAs is olive oil. The investigators therefore conduct an interventional trial in subjects with normal glucose metabolism, but increased HCL, fulfilling criteria for NAFLD. The investigation focusses on male participants to avoid sex-related differences in the results. The study will compare two isocaloric dietary interventions in parallel design, one containing mainly PUFA (canola oil), one containing only MUFA (olive oil). The intervention of 8 weeks is accomodated by dietary counseling (4 sessions). Metabolic outcome variables will be assessed with MR spectroscopy (liver fat), anthropometry (to check for stable weight and body composition) and euglycemic hepatic clamp (glucose metabolism/insulin sensitivity).

Inclusion Criteria: increased hepatic fat content (NAFLD) BMI between 30 and 35 kg/m² Exclusion Criteria: diabetes severe cardiac, pulmonary or gastrointestinal disorders hepatic disorders other than NAFLD alcoholism medication with metabolic side or main effects (e.g. statins)